Book Image

ARM?? Cortex?? M4 Cookbook

By : Dr. Mark Fisher
Book Image

ARM?? Cortex?? M4 Cookbook

By: Dr. Mark Fisher

Overview of this book

Embedded microcontrollers are at the core of many everyday electronic devices. Electronic automotive systems rely on these devices for engine management, anti-lock brakes, in car entertainment, automatic transmission, active suspension, satellite navigation, etc. The so-called internet of things drives the market for such technology, so much so that embedded cores now represent 90% of all processor’s sold. The ARM Cortex-M4 is one of the most powerful microcontrollers on the market and includes a floating point unit (FPU) which enables it to address applications. The ARM Cortex-M4 Microcontroller Cookbook provides a practical introduction to programming an embedded microcontroller architecture. This book attempts to address this through a series of recipes that develop embedded applications targeting the ARM-Cortex M4 device family. The recipes in this book have all been tested using the Keil MCBSTM32F400 board. This board includes a small graphic LCD touchscreen (320x240 pixels) that can be used to create a variety of 2D gaming applications. These motivate a younger audience and are used throughout the book to illustrate particular hardware peripherals and software concepts. C language is used predominantly throughout but one chapter is devoted to recipes involving assembly language. Programs are mostly written using ARM’s free microcontroller development kit (MDK) but for those looking for open source development environments the book also shows how to configure the ARM-GNU toolchain. Some of the recipes described in the book are the basis for laboratories and assignments undertaken by undergraduates.
Table of Contents (16 chapters)
ARM Cortex M4 Cookbook
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Setting up the ADC


The aim of this recipe is to configure the ADC in single-conversion mode and then convert the voltage set by the thumbwheel into a 12-bit digital value. We'll configure the ADC to generate an interrupt at the end of each conversion and write an interrupt handler to read the ADC and initiate a new conversion. The only task for our main function to perform is to output the ADC value to the LEDs, but as there are only 8 LEDs we can only display the most-significant 8-bits of the ADC value. We'll call this recipe adcISR_c5v0.

How to do it…

To set up the ADC follow the steps outlined:

  1. Open a new folder named adcISR_c5v0 and create a new project named adcISR.uvprojx.

  2. Select LED (API) from RTE Board Support but do not select A/D converter (we will write our own code for this). Set the CMSIS and Device software components as for previous projects. Be sure to select resolve so that the correct runtime environment (RTE) is included.

  3. Create an adcISR.c file (the main function) and enter...